The present invention relates to etching a silicon layer through a hard mask during the production of a semiconductor device. More specifically, the present invention relates to in-situ stripping of the photoresist after opening the hard mask.
During semiconductor wafer processing, features of the semiconductor device may be defined by a patterned hard mask. The semiconductor device features may be transferred into the hard mask using a photoresist and by plasma etching of the hard mask. After the features are transferred into the hard mask, the remaining photoresist on the hard mask may be removed.
Traditionally, separate equipments are used to open the hard mask and remove the photoresist. After the opening of the hard mask, wafers are removed from the plasma reactor and placed into a separate ashing equipment for stripping the remaining photoresist. In this case, another expensive equipment is needed solely for the stripping of the photoresist, which requires additional fabrication space and wafer processing time. Removing the wafers from the plasma chamber may cause wafers to come in contact with the environment, which may lead to modification of the etched surfaces and cause inconsistent wafer surface conditions before the stripping process.